Iraq will again take center stage in the Senate this week as Democrats push for passage of a war spending bill that includes troop withdrawal provisions that nearly all Senate Republicans oppose.

Debate on the $121.7 billion emergency spending bill, approved by the Senate Appropriations Committee on March 22, is expected to begin Monday.

Several GOP senators indicated that their party was unlikely to filibuster the supplemental over the Iraq language. They may not need to, because they appear to have the votes to strip the provisions.

The Senate action follows House passage March 23 of its $124.3 billion war spending supplemental (HR 1591), which included a timetable for troop withdrawal. The House bill passed by a narrow margin, 218-212, with one member voting “present.”

Senate Republicans say even if they are unable to strip the Iraq language from the bill, they are confident that Democrats lack the votes to override a threatened presidential veto of the supplemental.

“We will not filibuster the bill,” said Sen. John McCain, R-Ariz. “But we guarantee — the president has guaranteed his veto. And I’m sure there will be sufficient number of votes to sustain his veto.”

Still, it is a priority of Senate Republicans to remove the Iraq withdrawal provisions from the measure. The ranking Republican on the Senate Appropriations Committee, Thad Cochran of Mississippi, announced during the panel’s markup that he intends to try to strike the provisions, which would mandate the withdrawal of troops from Iraq starting 120 days after enactment, with the goal of completing the process by March 31, 2008.

Sen. Joseph I. Lieberman of Connecticut, an independent who caucuses with the Democrats but votes with Republicans on Iraq, predicted Cochran’s motion would prevail.

“I believe that we’re going to succeed in striking this harmful language from the bill on the Senate floor,” Lieberman said.

The withdrawal language mirrors a resolution (S J Res 9) offered by Senate Majority Leader Harry Reid, D-Nev., that the Senate defeated earlier this month, 48-50. Absent from that vote were McCain and ailing Democrat Tim Johnson of South Dakota. Johnson will not be back this week. But McCain — a strong opponent of legislation that requires or even advocates withdrawal from Iraq — will be, giving Republicans one more vote.

Sen. Ben Nelson of Nebraska, a conservative Democrat, voted against the Reid resolution on the floor. But he switched his position in the Appropriations markup when Democrats included language in the supplemental that would require the commander of coalition forces in Iraq to report to Congress on Iraqi compliance with political, economic and security commitments it has made to the United States.

Nelson would not say if he would vote to strike the Reid language from the bill on the floor. He suggested he might vote for the Republican motion if the bill retained the language on Iraqi commitments. “I would look very carefully at it,” he said.

Lieberman predicted Cochran’s motion would aim only at the language from Reid’s resolution.

Senate Minority Whip Trent Lott, R-Miss., said Democrats may have included the Iraq withdrawal language with the idea that once it was removed, Bush would be willing to sign a bill that contained billions of dollars in additional spending. “This really could be about getting their money,” he said.

Lott added that there was plenty of spending in the bill that he could support — such as for Hurricane Katrina recovery — but not as part of an emergency war spending bill. “This is about my country. I’m for my state and I’ve tried to get funding for my state. But when it comes to the military and men and women in uniform, that is a higher priority,” he said.

Though the White House has threatened a veto over the Iraq provisions and the extra spending, Senate Appropriations Chairman Robert C. Byrd, D-W.Va., said in a statement March 23 that he “rejected” that warning.

“The secretary of Defense has stated that the funding for the military and rebuilding Iraq is needed by the end of April. We will meet that goal,” he said.

“But the administration should place the same priority on rebuilding America’s Gulf region. The White House will pay to reconstruct Iraq, but apparently reconstructing Louisiana and Mississippi isn’t as important.”

The Senate will take up the House supplemental, but strike its contents and replace them with the language contained in the bill approved by the Senate Appropriations panel (S 965).

House Democratic leaders were confident heading into the March 23 floor vote and jubilant after its passage. The vote was widely viewed as a test of leadership for House Speaker Nancy Pelosi, D-Calif., and her ability to unite the Democratic caucus.

“As I have said from the beginning, the war in Iraq is a grotesque mistake,” Pelosi, D-Calif., said in a speech before the vote.

“Each member of the House will make a choice — the world is watching for our decision. Will we renew the president’s blank check for an open-ended commitment to a war without end, or take a giant step to end the war and responsibly redeploy our troops out of Iraq?”

In the end, 14 Democrats voted against the bill. Half were liberal lawmakers who thought it did not go far enough in bringing an end to the war quickly, and the other half centrists who considered the Iraq conditions overly restrictive.

Two Republicans voted for the bill — Wayne T. Gilchrest of Maryland and Walter B. Jones of North Carolina. Pete Stark, D-Calif., voted present.

President Bush reacted to House passage by saying the supplemental measure “has no chance of becoming law.”

“As I have made clear for weeks, I will veto it if it comes to my desk. And because the vote in the House was so close, it is clear that my veto would be sustained,” Bush said March 23.

Rep. Neil Abercrombie, D-Hawaii, reacted angrily to the veto threat. “He can’t veto it. He’s the one that’s caused the problem,” he said. “If President Bush wants to find out who’s not supporting the troops and undermining their capacity to fight, all he has to do is look in the mirror.”

House Republicans had been toying all week with offering language that would either cut the Iraqi conditions or eliminate both the conditions and the non-war domestic spending. Yet, they did not offer a motion to recommit, despite nearly united GOP opposition to the bill.

Republican leaders concluded such a motion would provide cover for conservative Democrats who could later tell constituents they voted for a no-strings-attached version of the bill.

“By not doing a motion, we get to hold these moderate and conservative Democrats accountable for the next two years,” one GOP leadership aide said.

In addition to keeping Democratic defections to just 15 on the House bill, counting Stark’s “present” vote, Pelosi managed to convince all the freshmen Democrats to vote for the supplemental.

The Speaker keeps close tabs on the concerns of the freshman class by meeting with the new members each Wednesday morning.

The sessions have been well-attended, often drawing 30 or more of 42 Democratic freshmen, according to a Democratic leadership aide. The class is nearly one-fifth of the Democratic caucus and represents a cross-section of its ideologies.

Jonathan Allen, Alan K. Ota, Susan Ferrechio and Alex Wayne contributed to this story.